In an office, for example, since natural outdoor light (sunlight) enters inside a building (room) through window glass or the like, a person in the building is dazzled in some cases. Thus, for example, in order to prevent a person from being dazzled during work or from a viewpoint of security and privacy protection, there is a case where a blind, a curtain, or the like is arranged in front of window glass. Thereby, it is possible to shield light entering through the window glass and prevent peeping the inside of a room through the window glass.
Currently, a method by which, by using a daylighting member having a microstructure for a slat of a blind, external light in the daytime is efficiently taken and radiated toward a ceiling in a room or the like has been proposed (for example, PTL 1).
As performance which is required for a blind, importance is attached to an angle adjustment function, storability, mechanical strength, thinness, and a lightweight property of a slat, or the like.
In PTL 1, a configuration in which an assembly configured by putting a light guiding film between a discolorable element and a light shielding element, each of which has a film-like shape, is provided in a slat via a seat is disclosed. With this configuration, strength of the assembly having a film-like shape is secured by the seat.